1. Field of the Invention
The present invention relates to a nanoparticle delivery vehicle, more particularly to a nanoparticle delivery vehicle having a phosphate moiety.
2. Description of the Prior Art
Selective targeting of cancer cells has limited success by application of modern chemotherapeutic methods. Paclitaxel (i.e., Taxol) is one of the most popular chemotherapeutic agents used nowadays for treatment of breast, ovarian, and lung cancers. Being able to promote tubulin assembly into microtubules, paclitaxel brings significant impact mainly because of its mechanism of action. On the other hand, its drawbacks come from the lack of tumor specificity and low solubility in water.
For improving the tumor specificity and low water solubility issues of anticancer drugs, Pero et al. (US. Patent Application No. 20030109500) administered a sufficient amount of a cytotoxic agent formulated into a phosphate prodrug form having substrate specificity for microvessel phosphatases. Microvessels therefore are destroyed preferentially over other normal tissues because the less cytotoxic prodrug form is converted to the highly cytotoxic dephosphorylated form.
However, it may not be sufficient for highly hydrophobic anticancer drugs to improve their hydrophilicity with single phosphate moiety, and the hydrophilicity issue still needs to be solved. Furthermore, the above-mentioned technique may not precisely deliver anticancer drugs to the position of cancer cells and may not be able to selectively target cancer cells in vivo.
To sum up, it is now a current goal to develop a novel drug delivery vehicle for improving the hydrophilicity of anticancer drugs and precisely delivering to the position of cancer cells.